2 files changed, 12 insertions, 7 deletions

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 81c287fad79d..dfd21cfdf579 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1630,12 +1630,17 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                         The default is to return 64-bit inode numbers.
 
         nfs.nfs4_disable_idmapping=
-                        [NFSv4] When set, this option disables the NFSv4
-                        idmapper on the client, but only if the mount
-                        is using the 'sec=sys' security flavour. This may
-                        make migration from legacy NFSv2/v3 systems easier
-                        provided that the server has the appropriate support.
-                        The default is to always enable NFSv4 idmapping.
+                        [NFSv4] When set to the default of '1', this option
+                        ensures that both the RPC level authentication
+                        scheme and the NFS level operations agree to use
+                        numeric uids/gids if the mount is using the
+                        'sec=sys' security flavour. In effect it is
+                        disabling idmapping, which can make migration from
+                        legacy NFSv2/v3 systems to NFSv4 easier.
+                        Servers that do not support this mode of operation
+                        will be autodetected by the client, and it will fall
+                        back to using the idmapper.
+                        To turn off this behaviour, set the value to '0'.
 
         nmi_debug=      [KNL,AVR32,SH] Specify one or more actions to take
                         when a NMI is triggered.
diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 41bd67f80d31..277dfaf2e99a 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -84,7 +84,7 @@ retry:
 /*
  * Turn off NFSv4 uid/gid mapping when using AUTH_SYS
  */
-static int nfs4_disable_idmapping = 0;
+static int nfs4_disable_idmapping = 1;
 
 /*
  * RPC cruft for NFS